Details:

The UA MK-1—short for Mode Kit 1—is an entire system of light, sleek, breathable warm-ups and core training gear that layers together to give you every advantage for any workout. Speed, agility, strength, cardio, in the gym, on the turf whatever you're doing, just build your kit and get to work.

Fitted: Next-to-skin without the squeeze.

It's French Terry you can actually work out in  the same comfort & warmth, but lighter & faster